This recurring series, Social Studies, takes a closer look at the social-media accounts of our most popular and prominent stars.

If you’re anything like us, it is rare to have a drinks date with a friend these days that doesn’t at some point touch on the Hadid sisters. Gigi, 21 years old and one of the most famous supermodels in all the land, and her younger sister, Bella, 20, also one of the most famous supermodels in all the land, seem to be everywhere at the moment. They are on the runway at the Victoria’s Secret Fashion Show in Paris; they’re on magazine covers left and right; they’re on your Instagram feeds; they’re on your tabloid covers. To be a pop-culture fanatic in 2016 is to be fluent in Hadid.

But Bella and Gigi—though just one year apart in age—have crafted quite different personas for themselves, and that difference is especially evident in their social-media presence. While Bella’s “brand” is more enigmatic and moody, Gigi’s is sunnier, bubblier and more straight-forward. Gigi is Coke; Bella is Pepsi. Bella is the woman your friends were all terrified of from afar—and whose approval they desperately sought at the same time. Meanwhile, Gigi was those same girls’ super nice, outgoing, and popular friend.

When it comes to Instagram followers, Gigi is far outpacing Bella, with—right now—26.7 million to Bella’s 8.6 million. Gigi now regularly garners more than a million likes per picture, and, anecdotally, her account is one of the “hottest” on Instagram (in the “your friends all follow her, too, and obsess over what she posts, as well” way). Gigi dates Zayn Malik; she’s friends with Kendall JennerandTaylor Swift (no small feat); and she is currently engaged in high-profile collaborations with the likes of Tommy Hilfiger and Reebok. She is, as they like to say, having a moment—and this is reflected in her social-media presence, as well. Every image she posts seems carefully crafted to work efficiently, whether it be to feature the details of a favorite runway look or share a recent behind-the-scenes shot from a cover shoot or serve one of her brand campaigns.

At first glance, Gigi is offering a pretty straightforward portrait on Instagram. In general—especially over the past year—the photos are mainly from the major events (the award shows, the runways, the fashion spreads). There’s a sunlit gloss to most of the pictures, too; everything looks like an advertisement for the Hadid lifestyle: carefree, bright and, metaphorically, in close proximity to the beach. Gigi is prone to crafting long essays as captions, thanking her family and team members after particular events, as if she were delivering an acceptance speech. They are earnest, and sweet, and while the long captions could come off as cloying (“I can’t wait to continue to grow and create with all of you, and to see what the future holds!!” ), she usually manages to toe the line.

But, wisely, Hadid does mix in some less “professional” shots, which lend the feed a slightly more “personal” touch (these posts are no doubt equally deliberate, though, in terms of their intended effect). There’s the stock-image shot of color-coordinated cereal (“weekend goals” reads the caption); there’s the Nutella spread in front of her on the dinner table; there’s the Snapchat-filtered shot and the “casual” bag snap. And yeah, it is unlikely many of us look like Gigi Hadid when we use Snapchat filters, but we at least know what it’s like to mess around with a Snapchat filter for 10 minutes when you’re supposed to be finishing something for work, and then deciding you actually really like how you look in it and saving it to your camera roll, and then waiting a few days before (maybe after a glass of wine) deciding to post it to Instagram. (On Twitter, Gigi will occasionally tweet about pop culture items like Making a Murderer; yes, she is, at times, just . . . like . . . us!)

She also earns “relatability points” with her frequent posts about her siblings—Bella, as well as aspiring model younger brother, Anwar. When she posts about them (“WORK” she wrote with a Bella runway picture), she at once seems selfless (the hard-to-please Instagram commentariat does not look kindly upon someone perceived as only posting pictures of themselves) and—and this is an insane point to spell out, probably—those posts remind us she isn’t just a celebrity astronaut, floating through space on her own, buoyed by paparazzi flashes and Instagram likes, but that she has a family that she’s almost definitely on a very-active group text with, too.

If Gigi’s Instagram comes off as closely curated, Bella’s is markedly . . . looser. Gigi is handing in her assignments a day early, and with extra credit completed; Bella is turning in the take-home test a day late and hastily finished (though still getting close to the same mark, because she has an innate understanding of the material). Bella regularly posts ‘grams without captions, something Gigi does very rarely. She’ll post a few photos from the same event in a row (either with short captions or none at all), and it is unclear sometimes what, if anything, she is trying to “say” with them, other than just “this is a cool picture” (many Instagram accounts are fueled by much lesser underpinnings, of course)—I guess she really likes her outfit in this shot, you’ll think, and usually it is a really good outfit.

This is not to say Bella’s Instagram is a completely incomprehensible journey or purely haphazard collection of photographs. She still checks off many of the key boxes associated with a celebrity account: she promotes her brands; she offers up photos of herself just being Bella that you won’t find anywhere else. She is just giving us fewer data points to use, less of her. For example, she posted a photo of herself biting her finger on set this past week. No caption. She has two brands tagged. You can almost imagine her glancing at this photo, on a phone handed to her by an assistant, and murmuring, “Sure.” (“What do you want the caption to say, Bella?” “I . . . you know . . . whatever.”) When she does decide to add a caption and offer a bit of verve (“woman of business” she wrote with this shot), it’s never quite the caption you expect. She posts photos of her family, too, though they’re Bella-fied: she posted one of her and Gigi with the caption “u.”

Bella is not very easy to pin down, and her less-organized use of Instagram only serves to heighten the sense of mystery around her. She doesn’t handle things much differently on Twitter, either (she tweeted the word “bye” on October 31; on October 14, “everyday shit . . . every night shit . . . ”). She is very much the younger sibling. Gigi is walking the trail in a straight line, breaking the course record; Bella is ambling a bit more, taking her time and trying things out. (And Anwar, younger brother, is even more offbeat, at least based on his quirky, artistic-leaning Instagram account.)

Like Kendall and Kylie Jenner, Gigi and Bella’s combined force as a unit helps both of them individually. America loves the mixture of great fame and beauty with the intrigue of familial bonds and dynamics. While Gigi’s posts might carry a certain level of electricity (the buyout pop single) and Bella’s are at a slightly lower voltage (the moodier alt-radio track), that only works to their joint advantage. After all, sometimes you want the Coke, and sometimes you want the Pepsi. Now, what if you could enjoy both at once?

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